Together the spondyloarthropathies form a group of overlapping chronic inflammatory rheumatologic diseases that show a predilection for involvement of the axial skeleton, entheses (bony insertions of ligaments and tendons), and peripheral joints. They also may involve extraskeletal structures, especially the eyes, lungs, skin, and GI tract. These diseases are strongly associated with the HLA-B27 gene, but they lack association with rheumatoid factor (RF) and antinuclear antibodies.1
The spondyloarthropathies include ankylosing spondylitis, psoriatic arthritis, reactive arthritis, arthritis of inflammatory bowel disease (IBD), and undifferentiated spondyloarthropathy. They are more common than previously recognized. Recent data from Europe and Asia suggest that as a group, the spondyloarthropathies might be as common as rheumatoid arthritis (RA); in Europe, the prevalence is 0.5% to 1%.2-4
Because there are no diagnostic criteria for the wider spectrum of the spondyloarthropathies, the diagnosis is based primarily on clinical findings. 1,2,4-8 European Spondylarthropathy Study Group (ESSG) classification criteria are used frequently to assist the clinical diagnosis (Table 1).9 Early diagnosis has become much more important in recent years as more effective therapeutic options have become available.
In this article, we describe the specific clinical entities in the spondyloarthropathies and their common laboratory and radiological features. Then we outline a variety of management strategies, including nonpharmacological modalities, pharmacological therapy, and ophthalmological or surgical referral.
Ankylosing spondylitis. The prototype of the spondyloarthropathies, ankylosing spondylitis primarily in- volves the sacroiliac joints and spine (Figure) and, often, the hip and shoulder joints; patients typically present with chronic inflammatory back pain.2,8 Symptoms usually start insidiously when patients are in their late teens or early 20s; men are affected roughly twice as frequently as women.
Patients who have ankylosing spondylitis may awaken late at night or very early in the morning because of back pain and stiffness, which is eased with physical exercise or a hot shower. Enthesitis may cause pain and tenderness over the anterior chest wall, spinal processes, iliac crests, and sites of bony insertions of the Achilles and patellar tendons and plantar fascia. Peripheral arthritis, usually monoarticular or oligoarticular, is less common in primary ankylosing spondylitis than in “secondary” ankylosing spondylitis (in the context of psoriatic arthritis, reactive arthritis, or IBD).